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El.-d- 14—C-1 I200 6.F�9..9adsoti CA P-)-d Ha 130003.00 NP 3 the areas of concern. The clean fill material (gravel) from the original excavation was removed and isolated on site prior to excavation. Ramp areas were excavated to facilitate deeper excavation and collection of the soil samples. The extent of the excavation and former tank locations are depicted on Figure 2. A Photoionization Detector (PID) along with visual and olfactory methods were utilized during excavation to assist in evaluating the lateral and vertical extent of soil impaction. PID readings ranging from 100 to 400 parts per million (ppm) and petroleum hydrocarbon odor indicated that residual petroleum hydrocarbon impacted soils existed in the area of the former dispenser between 12 and 21 feet below grade, on the southwest wall and bottom of the 10,000 tank area and on the south side and middle bottom of the former 500 gallon tank area. Excavation continued until all physical evidence (PID readings below 0.5 ppm and petroleum hydrocarbon odor) was absent. A total of 12 samples were collected for PID screening; six from the south wall, the southwest wall, the south corner and bottom of the 10,000 tank area; two from the southeast side of the 10,000 tank area; and a total of four samples from the 500 gallon tank area east and west sides and bottom. Petroleum hydrocarbon impacted soil was underlain and covered with plastic sheeting pending laboratory analysis. Following excavation, confirmation samples were collected under the direct • supervision of Ms. Diane Hinson of SJCEHD. Sample selection was based upon collecting samples from the areas of concern listed above and where soil impact had been noted during excavation activities. A total of seven sidewall and excavation bottom samples were collected. The soil sampling locations are depicted on Figure 2. Samples were collected from the excavator's bucket three inches below the surface of the soil. The samples were collected into prewashed brass liners. Each liner was sealed with a Teflon sheet and plastic caps, sealed in air-tight bags, and preserved on dry ice pending shipment to Zymax Envirotechnology, Inc. Laboratories (DHS Cert. #1717) in San Luis Obispo, CA. Sample description and sample IDs are included in Attachment 1. Soil samples were transported under chain-of-custody to the laboratory for analysis of BTEX and TPHG by EPA method 8260. Upon SJCEHD's recommendation the laboratory was directed (as noted on the chain of-custody) to analyze any sample for TPHD by EPA method 8015 that eluted late peaks on the chromatogram (which is an indication of longer chain hydrocarbons). Stockpiled soil samples were collected and analyzed for BTEX and TPHG by method 8260 and for Reactivity, Ignitability, Corrosivity, and Title 22 toxic substances. Two 4-sleeve composite samples were collected from the stockpiled soil (one per 75 cubic yards of soil). An appropriate disposal and/or remediation plan will be developed based on the analytical data. Subsequent to excavation activities, the pit was be backfilled with the stockpiled fill material supplemented by clean imported fill. PAR•0593.FNL